Fuel-saving attachment for furnaces



1.1-. A. MILLER. v FUEL- SAVING ATTACHMENT FOR FURNACES.

APPLICATION FILED JULY 191 1919- 1,379,873. Patented'May 31, 1921.

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FUEL SAVING ATTACHMENT FOR FURNACES.

APPLICATION FILED JULY 19, I919.

Patented May31, 192 1.

2 SHEETS-SHEET 2- Q llT/VENTOR t ATTORNEY rein JOHN J. A. MILLER, or DENVER, COLORADO.

FUEL-SAVING ATTACHMENT FOR FURNACES.

' To all whom it may concern:

Be it known that 1, JOHN J. A. MILLER, a citizen of the United States of America, residing at the city and county of Denver and State of Colorado, have invented anew and useful Fuel Saving Attachment for Furnaces, of which the following is a specification.

This invention relates to improvements in fuel saving attachment for furnaces.

=The object of the invention is to provide an attachment for the doors of'all classes of furnaces, whereby a regulated supply of heated atmospheric air is admitted to the combustion chamber of the furnacefor a predetermined period after the coaling operation, the said air being discharged in a thin sheet over, and a slight distance above the coal bed, by which it is intimately mixed with the combustible gases and the floating particles of carbon and tar, thus causing complete combustion of these particles, and the consequent elimination of the unconsumed product, or smoke.

Further, to provide an attachment of this character, which can be applied to furnace doors of the commonly employed type, at a relatively small expenditure of time and expense, and which effects a maximum saving of fuel, together with the; practical elimination of smoke.

Further, to provide an attachment for furnace doors, for the purpose above stated, which comprises an air receiving chamber, a damper for admitting a volume of air thereto for a predetermined period after the coaling operation and thereafter limiting the air supply to a predetermined quantity, the said chamber having an outlet into the combustion chamber, the area of which can be increased or diminished to meet conditions, whereby a regulated supply of air can be admitted to the said combustion chamber in such manner as to intimately mix with the combustible gases therein, and thus effect complete combustion of the fuel.

These objects are attained by the mechanism illustrated in the accompanying drawings, in which: I

jFigure 1 is a vertical, longitudinal, sectional view, through the fire door and a portion of the front wall of a furnace, showing the improved device attached to the said fire door.

Fig. 2 is a front view thereof the damper releasing lever being in the position it Specification of Letters Patent.

1919. Serial No, 311,946.

reaches immediately prior to releasing the said damper Fig. 3 is a side View of the same.

Fig. & is a rear view of the air heating chamber.

Patented May31, i921.

Fig. 5 is a front View of the automatically operating damper which admits air to the I heating chamber.

Fig. 6 is a central, longitudinal, sectional view of the same.

x F 1g. 7 1s a SlflGVlGW of the lever operated arm for turningthe damper to an open po-- sition. I r

F ig.8 is a perspective view of one of the adjustable nozzle sections for area of the air outlet; and

Fig, 9 is a top view of the gravity lev r for raising the arm shown lIl Fig.7, and for effecting the release of the damper whereby the same is permitted to turn to a closed position.

Visible furnace smoke can only be abated by effecting complete combustion in the furnace, of the floatingparticles of carbon and tar, and this, complete combustion is accomplished only by supplying air suflicient for the complete oxidation of all combustible matter, and the'intimate mixing of the air with the combustible gases and the floating particles of carbon and tar. To bring about this result, air in large quantities should be admitted over the fire immediately after coaling and this quantity should be gradually reduced as the distilla- The improved furnace door attachment is adapted to meet these requirements by means of a combination of elements, which are arranged and constructed as follows:

Referring to the accompanying drawingz-The numeral 1 indicates the front wall of an ordinary furnace, and 2 the fire door, to which the present invention is secured. These doors, as ordinarily constructed, have a circular group of air inlet holes, which are opened or closed by a damper, and in order to attach the invention, that part of the door surrounded by the circular group of holes is first removed, leaving a circular opening 3,-in the door, as shown in Fig. 1, such an opening being formed in new doors to which the attachment is to be secured. i

A short air inlet pipe, 4:, is inserted through this hole, and this pipe is centered varying the r lever passes,-and in which it is secured by a pin, 31, as shown in Fig. 2. The upper portion of the arm passes through a guide,

I 32, and the upper end of the arm is adapted to engage the tappet, 17, and swing the damper to the position shown in Fig. 2, when the lever, 21, is raised by the fireman, which is done when he opens the firedoor to shovel in coal.

The lower end of the arm, 29, terminates in a foot, 33, which is adapted to be engaged by a projection, 34, on a hand lever, 35, which is pivotallly secured to a bracket, 36, which is bolted to the fire door. 'The lower end of the hand lever extends beyond the lower edge of the door, and this; end may be either engaged by a shovel in opening the door, or it may be grasped by the fireman, and the lever is swung around until a stop, 37, on its upper end engages the door, when further turning of the lever is prevented, and by giving the lever both a pulling and lifting action, the door latch,

'38, is released from its keeper 39 and the door is swung open.

When the stop, 37 engages the door, the arm, 29, is raised high enough to swing the tappet to the position shown in Fig. 3, and open the damper, D, and the damper remains open until the lever, 21, drops to its lowermost position, when the roller, 23, in its inner end engages a cam, or'projection, 40, on the blade spring, 19, by'which the spring is sprung or forced out far enough to disengage the shoulder, 14, on the damper rod, 12, thus permitting the damper to swing to a closed position.

If it takes on an average about half a minute to fire the furnace, and it has been found that the damper should be left open for about three minutes after firing; then, the spring, 28, should be given a tension by the bolt, 27, that will retard the rotation of the gear wheel 26, to such an extent that the lever will require-three and onehalf minutes to swing from its raised position to its normal or horizontal position.

The downward swinging movement of the lever is limited by the engagement of the foot, 33, on the arm, 29, with the projection, 34, on the hand lever, 35, and this occurs after the roller, 23, engages the cam, 40, on the blade spring, 19, as will be understood by reference to Fig. 2. In timing the drop of the lever, 21, the weights, 24, are also adjusted on the lever to assist in determining the drop.

The air box, 8, is rectangular in cross section and is preferably made in two sections, the forward section 8*, being semicylindrical in form, and being made of material that will stand continuous high temperature. This section is provided with an air outlet slot, 41, through which air is discharged above the coal bed into the combustion chamber, 42. The area of this slot is adapted to be contracted, when necessary, by nozzle sections, 43, which are of the same length as the slot, 41, and have overlapping ends which permit the sections to slide one upon the other, as will be understood by reference to Fig. 4. Each of these nozzle sections is formed with a curved plate member, 44, which conforms to the curvature of the section 8 and eachmember, 44, is provided with slots, 45, through. which pass screws, 46, which are screwed into the section 8 By partially unscrewing these screws, the nozzle'sections can be adjusted to vary the. size of the slot, '41, and the screws are then turned "to clamp the members, 44, to the section 8, to hold the sections in their adjusted positions. The nozzle. has'aslight downward inclination from the airbox, in order to direct the air against the coal bed, and the air isrheatedto a-high temperature .in the air. box before passing out through the nozzle. The upper nozzle section may be somewhat longer than the lower section in order tonmore effectively directthe air over the coal bed, and the nozzle prevents diffusion of the air, which is delivered over the'coal bed in a thin sheet, causing it tothoroughly mix with the-combustible elements and thus insure complete combustion. i

By constructing the air. box in two sections, the section 8 which is subjected to the greatest heat, can be removed, when nec- I essary,-and replaced with a new section.

Having described my invention, what I claim as new and. desire to secure .byLetters Patent, is: a i

1. In combination with a furnace'door, of means defining anairpassage there-, through, means for controlling the flow of air therethrough, means operative when the door is being opened to actuate the controlling means so as to permit free passage of air, means tending to hold the controlling I means in open position, means tending to move the controlling means to closing position and time-controlled means set for operation when the door is opened for automatically releasing the controller-holding means.

2. In combination with a furnace door, of means definingan air passage therethrough, a damper for controlling the flow of air therethrough, means for opening the door, means in cooperative relation with the said opening means for effecting the opening of the damper when the door is opened, means tending to hold the damper in open position, means tending to close it and time- 1 controlled means in cooperative relation with the door-opening means and adapted to be set, when the door is being opened, to automatically release the damper-holding means.

1 3. In combination with a furnace door, means defining an air passage therethrough, a damper for controlling the flow of air therethrough, a handle having angular play for opening the door, means for translating the angular motion during opening of door for opening the damper, means tending to hold the damper in open position, means tending to close the damper, time-controlled means for automatically releasing the said damper-holding means and means for translating the angular motion of the handle to said time-controlled means to set it for operation when the door is opened. 7

4:. In combination with a furnace door, means defining an air passage therethrough, a damper for controlling the flow of air therethrough, a handle having angular play for opening the door, an element in the path of movement of the handle for opening the damper, means tending tohold the damper in open position, means tending to close the damper, a pivotally mounted lever connected with said element andadapted to be turned when the handle is moved to open the door, means on the lever for causing it to return to its normal position, means for retarding the returning motion and means 01, the lever adapted to engage, near the end of its returning motion, the damper holding means to release it.

5. In combination with a furnace door, means defining an air passage therethrough, a damper for controlling the flow of air therethrough, a handle having angular play for opening the door, a weighted crank on the damper for operating it, an element in the path of motion of both the said handle and the crank and so related thereto that upon moving the handle to open the door the damper is opened, means for frictionally holding the damper in open position, a pivotally mounted'lever connected to the said element and adapted to be angularly moved thereby when the handle is operated, means for causing the lever to return to its normal position, meansfor retarding such returning movement and means connected with the lever to act, near the end of the returning motion thereof, upon the said frictional means to release it.

6. In combination with a furnace door, means defining an air passage therethrough, a damper for controlling the flow of air therethrough, a handle having angular play for opening the door, a lever pivotally mounted on the door in a normally horizontal position, a crank on the damper for operating it, an upright element loosely mounted upon the said lever in the path of motion of the handle and the crank, the parts being so related that when the handle is moved to open the door, the said element is moved upwardly into contact with the crank causing the damper to open and the lever is turned upwardly out of its normal position, means for frictionally holding the damper in open position, means for returning the .lever to its normal position, means for retarding such return movement and means connected with the lever to act, near the end of its return motion, upon the said frictional means to release it.

In testimony whereof I afiiX my signature in presence of two witnesses.

JOHN J. A. MILLER.

Witnesses:

Gr. SARGENT ELLIOTT, ELIZABETH SMITH. 

